Ring-grinding machine



Feb. 14, 1928. 1,659,092

R. D. GARDNER RING GRINDING MACHINE Filed April 10, 1922 4 Sheets-Sheet 1 Feb. 14, 1928. 1,659,092

R. D. GARDNER RING GRINDING MACHINE Filed April 10. 1922 4 Sheets-Sheet 2 5 Q Q 7 rage/ 2507 Mp/a Z) Gardne Feb. 14, 1928. 1,659,092 R.D.GARDNER RING GRINDING MACHINE Filed April 10, 1922 4 Shee ts-Sheet 3 Feb. 14, 1928.

R. D. GARDNER RING GRINDING MACHINE Filed April 10, 1922 4 Sheets-Sheet 4 Patented Fa. 14, 1928.

UNITEDiSTAT-ES 1,659,092 PATENT OFFICE. I g

RALPH n. GARDNER, F 311L011, WISCONSIN, ASSIGNOR or ONE-THIRD To EDWARD s. GARDNER AND ONE-THIRD T0 Joan NIELSEN.

RING-GRINDING MACHINE.

Application filed April 10, 1922. Serial 110.651.,008.

This invention pertains to grindingcmachines, and while the principles thereof may be advantageously employed in machinesadaptedto operate upon various articles, I s have chosen to illustrate the invention herein as embodied in a ring grinding machine adapted to grind the sides or faces of piston rings so as to bring the rings to a uniform predetermined thickness and impart a finish to thesefaces. v

The present invention is an improvement upon the machine disclosed in my Patent $51,416,952, issued May 23, 1922,, and its primary purpose is to provide a machinepwhich will be entirely automatic in its operation and one which will be reliable, durable, efficient and accurate.

With these and other objects in view, my

so that theywill beoperated upon by vari-- 3o ous portions of the grinding wheels, and for controlling these rings intheir movements and during the grinding operations to insure accuracy in grinding and a minimum likelihood of injury to the wheels.

Other objects and advantages ofmy invention should be readily appreciated as the same becomes better understood by reference to the following description, when considered in connection with the accompanying drawings:

Referring to the drawingsvzl Fig. 1 is a front elevation of a machine embodying my invention; 7

Fig. 2 is an end View thereof looking toward the right at Fig. 1;

Fig. 3 is a rear elevation of the machine.

Fig. 4 is a sectional view on theline 4+4 of Fig. 2; 7

Fig. 5; is a sectional of Fig. 4; I 1

Fig. 6 is a sectional view through one of the adjustable wheel mountings;

Fig. 7 's a top plan view of the machine;

By reference to the drawings, it will be observed that themachine comprises essenview on the line 5.v5

tially a frame or base portion 4, upon which adapted to reciprocate acarriage 6 provided with suitable hearings. in which the two carrying shafts 7 are Fjournaled. These shafts carry at their inner ends the grinding tools or wheelsS in the shape of abrasive discs which are'disposed inopposed relation to each other, as will be apparent from Figs. 1 and 7. The shafts may be rotated by any preferred mechanism to impart suitable rotary movement to the grinding tools, but in the present instance I have shown each shaft as equipped with a driven pulley 9 adapted to be driven by a belt. These shafts are so driven that they rotate in opposite -.direc tions with the result that the grinding wheels are rotated in opposite directions thereby distributing the strains imposed upon a ring being ground between them. In order that the shafts may be adjusts to absolute axial alinement so as to dispose the grinding faces of the wheels in parallelism, the bearings '11, in which each shaft is journaled, are carried upon a base12 which is secured to its respective bed 6 by three bolts, 13, 14 and 15, respectively. A stud 10 serves as afulcrum, and the bolts 14 and 15 extend through slots in the base about the stud for adjustment and a'linement purposes,

and in order to secure with accuracy the final slight adjustments, I have mounted upon the carriage 6 a pair of'ears or lugs 16 .each equipped with a set screw 17, by means of which the final adjustments may be given to the bed before the bolts 1 1 and 15 are finally tightened. The details of the mountings of bolts 13 will be later described.

The carriages 6 with the grindingtools mounted thereon as above described, 1 are moved toward and from each 'other' bysuitable mechanism operated from *a rock shaft 18, which in turn is normally urged inone direction to cause an approaching movement of the grinding wheels by an arm 19 fixed thereto andiactuated by a weight 21 suspended therefrom. The pressureexerted by the grinding tools maybe varied; by increasing or diminishing the number of the weights 21; The connecting mechanism between the rock shaft 18 and the two carfixed upon. a continually rotating shaft 23 and engaging a stud 24; projecting laterally from an arm 25 also fixed on the shaft 18 but at the opposite side of the machine from the arm 19. Manual actuation of the shaftagainst the action of the weights 21 may be effected when desired by means of a hand lever26 fixed on the shaft 18 adjacent to the, arm 25. The shaft 23 with the cam thereon is driven from a train of gearing in the gear boX 27, to which power is trans mitted through a drive shaft 28 from a variable speed pulley 29 driven by a belt in the usual manner.

The approaching movement of the grin-file ing tools is limited by an abutment bar 31 carried by one of the carriages 6 and adapted to abut against an abutment screw carried by the other carriage and equipped with a micrometer adjustment 33 by which the limitation of the approaching movements of the tools may be regulated to a fine degree of nioety, as is explained more in detail in my co-pendiing application to which refcronce has previously been made.

The rings to be ground, indicated by ref erence character 34, are disposed on edge in a magazine comprising the two bars 35 and 36 extending longitudinally of the ma chine and supported upon suitable brackets. Upon these bars there is slidably mounted. a follower head 37. connected by a cable 38 which is trained over pulleys 39. 41 and 42, with a weight 43 which normally urges the follower head toward the right, viewing Fig. 1, pushing the rings before it into position to be transferred from the magazine to the grinding tools, as will be later explained. A latch 40 pivoted on the follower head is adapted, when the head. is retracted to its outermost position, to drop behind the outer end of the bar 36 or into a notch provided therein whereby the head is locked against movement, while the magazine is being rcplenished. When the latch is released, the head will be urged under the influence of the weight 43 lLOWZlIdl the rightto move the rings successively into transferring position, as previously mentioned. For the purpose of precluding the head from intersecting the path of the transferring ram, it is equipped with an adjustable abutment screw 4% adapted to abut against a bracket 45, by which movement of the head toward the right,

viewing Fig. 1, is limited.

Upon the frame of the machine, at the delivery end of the magazine, there is mounted a guide-plate 4E6 equipped with guide-bars s? and i8 between which and the plate the transferring ram 49 is adapted to reciprocate. This ram'is thinner than the rings to be operated upon so that it will not engage nore than one ring at each transferring movement.

. The plate 4L6 is provided with an elongated horizontally disposed slot 51 through which a connecting stud establishes 0perative connection between the ram 19 and its operating lever 53, which is fulcrumed at 54 and equipped with an arm 55 carrying a weight 56 bywhich the lever is normally urged in a counter-clockwise direction, viewing 2, to project the ram 4-9 to the left, viewing this figure, between the grinding wheels. Above its fulcrum the lever 53 is provided with a cam follower 57 which rides against a cam 58 mounted upon the shaft 23, and at each revolution of this shaft the lever 53 is swung about its fulcrum in a clockwise direction to retract the ram 49, so that its inner end is positively actuated to withdraw it past the delivery end of the magazine permitting the foremost ring in the magazine to be pushed into the path of the ram so that upon the next inward or transferring movement of the ram, this ringis carried or pushed by the ram into the first grinding position between the tools. During the operation of the grinding tools thereon the rings are supported upon av work support or bar 59 extending transversely between the grinding wheels and adjustably supported at its rear end upon a. standard 61. The rear portion of this support is partially cut away as indicated at 62 to facilitate the delivery of the rings from between the wheels. Above the support there is adjustably carried upon the standard 61 by a bolt 63 a retaining or or member 6 1 provided at intervals corresponding with the diameters of the rings being ground, with arcuate recesses 65, this mem her being adapted to rest by gravity upon the rings so as to hold them successively in substantially the position shown in Fig. 2 during the grinding operation. The forward end of this member is provided with an upwardly extending bolt 66, projecting through a guide 67 and equipped with adjustable nuts 68 which, by engagement with the guide 67, limit the downward movement of the forward end of the member. Should the weight of the member itself be insufiicient to retain the rings against displacement, weights to the requisite amount may be disposed upon the bolts 66 above the nuts 68. To facilitate entrance of the rings beneath the member 64, its forward end is preferably chamfered 06 as indicated at 69. Accommodation of the position of the member to rings of different sizes may be effected by adjusting the positionof the nuts .68 and also its fulcrumed end which is suspended by an adjustable "rod 70 from a bracket 71 secured to the standard 61 by the bolt 63. Normal adjustments of the member 64 may be obtained bythreading the nut 72 upwardly or downwardly on the rod 70 and further adjustment, if required, may be secured by loosening the bolt 63, and adjusting tl e bracket 71 bodily up or down on the standard 61. 1

During the operation of the machine the rings inthe magazine are urged bythe follower. successively into the path of the reciprocating ram 49, by which they are transferred into position between the grinding wheels, These wheels are alternately advanced toward each other and. retractedby alternate action of the weight 21 and cam 22, and the parts are so timed that the rings are moved into position between the wheels, while they are in their retracted position, and during the grinding operation the ram is o erated to transfer another rin as soon as the wheels .areseparated. At each actuation of the ram the ring transferred from the magazine into grinding position will push the nextpreceding ring one step farther along between the wheels, and this operation-is repeated at each actuation of the rain with the result that each ring is successively disposed in four different positions, and is operated upon by the wheels four times before it is discharged from between the wheels. The number of positions that each ring will assume between the grinding wheels may vary however and is obviously dependent on the size, of the rings and the lengthof stroke of the rain. hen a ring is discharged from; itsfinal. grinding position, it rolls down the incline 62 andjinto a chute 73 by which it is discharged from the machine, v s.

For the purpose ofdressing the faces of the wheelswhen this becomes necessary, I have mounted atthe rear of the machine upon a bracket 74 a wheel dresser carrier rod 75 carrying at its forward end a wheel dresser 76 normally disposed outside the perimeter of the wheels as shown in Fig. 2.

hen it becomes desirableto employ the dresser, the rear hinged portions 77 of the wheel housing are swung out of operative position and the dresser is slid longitudinally in its support into position between the wheels, as will be later explained. In order to permit theintroduction of the dresser into position the wheels are first backed off or separated, and when the dresser has been properly positioned, they are permitted to approach until one'of the wheels, towards which the dresser is faced, is disposed sub stantially in proper position to be operated upon. An arm 78 which is normally loosely disposed on the shaft 18 is then clamped thereto with an adjustable abutment screw 79 carried at its outer end disposed substantially in contact with an abutmentshoulder 81 onthe machine frame The screw 7 9 may then be adjusted to rock the shaft18-slightly I ing orseparating movementof the wheels will take place. Preferably, however, the clutch 82 is thrown out imtead'to stop the cam 22 with its low portionbeneath the arm 25, so that the grinding wheels will not be reciprocated but will revolve invfixed rela tion to each other, determined by the. adjustment ofscrew 79. When one of the wheels has been properly dressed, the dresser is turned to face the other wheel, and since the a 'aproaching movement of both wheels is controlled by the position of the adjusting screw 79, it will be manifest that the second wheel will be dressed exactly like the first one, and, therefore, all danger of over or under dressing one wheel relatively to the other is entirely eliminated.

The wheels'as previously mentionedare entirely enclosed in a housing, except for openings therethroug h to permit of the introduction and discharge of work to be operated upon, and for the purpose of withdrawing the dust resulting from the grinding operation, a conduit, is provided in the base of the machine and is preferably conjnecte'd withan exhaust fan which withdraws alldust and line particles from the wheel housing, thereby not only protecting the machine against the .entranceof these dust and lit particles intothe bearings, but also reiieving the operatorofthe annoyance usually occasioned by dustand grit particles'in the air around these machines. I In order that the machine may be quickly stopped whenever it may be desirable, a clutch 82 is preferably interposed inthe shaft 28 and adapted to be actuated by a control lever 83 disposed in position accessible to the operator.

The wheel dresser carrier rod 75 isslidably mounted in an elongated bearing 84 provided with bushings 85, and is provided withoppositely positioned kerfs 86 and 87 respectively adapted to receive the inner end of a pin'88 by which the rod is held against rotation' A set screw 89 serves to lock the pin in position. \Vhen one ofthe wheels is to be dressed the wheels are separated as previously explained, and the rod 75 is slid in its bearingsto bring the dresser 7 6 within the perimeter of the wheels. After this wheel has been dressed. the pin-88 is withdrawn, the rod 7 is rotated through an arc of 180 to. present the dresser toward the face of the other wheel whereupon the pin The arm 25 may be ing wheels will be revolved, but no approach- &

is projected into the other kerf 87 to hold the dresser in proper position to dress the other wheel.

The adjustability of'the grinding wheels for alignment and other purposes has been explained in a general way, but for further details attention is directed to Fig. 6. The bolt 12-} extends loosely through a washer 91 disposed above the base 12 and through a bearing nut or stud .92 adjustably threaded into a tapped opening in the base and is screwed at its lower end into a tapped opening in the carriage 6. he loose fit of the bolt in the stud 92 permits of limited angular adjusting movements of the b: about the fulcrum stud 10. Should it become desirable to elevate or lower the outer end of the base relatively to the inner end, the bolt 13 may be slightly backed otl whereupon by turning the washer 91 with a spanner wrench the stud 92 is raised or lowered as the result of the rotation imparted thereto by the pins 93 projecting from the washer into a transverse slot 94 in the stud. This manner of mounting provides in effect a pointand a line support for the base upon which the base may be adjusted laterally and vertically to properly position the grinding wheel. 7

It should be apparent from the foregoing that I have provided a machine which is entirely automatic in its operation, one which will feed the rings to be ground automatically and successively into grinding position, that the rings are progressively moved between the grinding wheels in a step by step movement so that they are subjected to various portions of the wheel surfaces, that when finally finished they are automatically delivered from the machine, that the position of the wheels may be accurately adjustedto dispose them in exact alinement, that provision is made for the assurance of accurate dressing of each wheel, and that many other advantageous features are contemplated by my invention, which may be embodied in machines differing materially in their structural details from that illustrated and described, and without departing from the essence of the invention as defined in the following claims.

I claim:

1. In a grinding machine having a rotatable grinding wheel presenting a grinding face, a work supporting bar extending across a portion of said face, a Work retaining member positioned above said bar, said member being supported to yield upwardly when work is received between it and said bar, and means for varying the minimum distance between said bar and member.

2. In a grinding machine having a rotatable grinding wheel presenting a grinding face, a work supporting bar extending across a portion of said face, awork retaining member supported above said bar and to float downwardly toward said bar to a predetermined position with respect thereto, and means for varying said predetermined position.

3. In a grinding machine having a rotatable grinding wheel presenting a grinding face, a work supporting bar extending across a portion of said face, a work retaining member positioned above said bar, said mema portion. of said face, a work retaining v member supported above said bar and to float downwardly toward said bar to a predetermined position with respect thereto, means for varying said predetermined posi tion, and means for increasing the pressure of said member upon work held between it and said bar.

5. in a grinding machine, the combination of a pair of opposed grinding wheels having their planes of rotation in substantially parallel planes, a magazine at one side of said wheels having its delivery end dis posed substantially in a plane extending between said wheels, a follower for moving work pieces in said magazine toward the delivery end thereof, means for locking said follower in inoperative position, and mechanism for transferring said work pieces in succession from the delivery end of said magazine into operative position between said grinding wheels.

6. In a' grinding machine, the combination of a pair of opposed grinding wheels having their planes of rotation in substantially parallel planes, a work magazine, a follower movable longitudinally thereof, means for lockingsaid follower in retracted posit-ion, means for limiting the movement of said follower toward the delivery end of said magazine, and means for transferring work pieces in succession from the delivery end of said magazine into position between said wheels.

7. In a grinding machine, the combination of a pair of grinding wheels, a work supporting bar extending transversely between said wheels, a work retaining member positioned above said bar, means for adjustably supporting said member and permitting upward yielding movement of the member to accommodate work pieces, said member being provided on its lower face with work receiving recesses, and means for feeding work pieces successively between said bar and retaining member.

lull

v 8. In a grinding machine, the combination of a pair of grinding Wheels, a work supporting bar extending transversely between said Wheels, a Work retaining member adjustably mounted above said bar, said member being provided on its lower face with a plurality of Work recelvlng recesses,

a magazine, means for feeding Work pieces in succession from said magazine into posi tion between said bar and retaining memher, the introduction of one Work piece being adapted to discharge another piece at the opposite side of thewheels, and a chute for delivering said discharged pieces.

RALPH n. GARDNER. 

